Figure 5.

Single-nucleotide insertion after uracil excision is template-dependent. Duplex DNA containing a U residue at the 5′ end-labeled upper strand paired to G (left panel) or A (right panel) was incubated at 30°C for 3 h with Arabidopsis cell extract and a single dNTP, as indicated. Reaction products were separated in a 12% denaturing polyacrylamide gel, and then detected by fluorescence scanning. Fragments corresponding to 28 and 29 nt are indicated by arrows.